求翻译求翻译，超级感谢！！！

(1) mobile phase A: mix 20 volumes of a mixture of 19 volumesof 1,1-dimethylethyl methyl ether R and 81 volumes ofacetonitrile for chromatography R with 80 volumes of a0.04 per cent V/V solution of phosphoric acid R;

(2)mobile phase B: mix 20 volumes of a 0.04 per cent V/Vsolution of phosphoric acid R with 80 volumes of a mixtureof 19 volumes of 1,1-dimethylethyl methyl ether R and81 volumes of acetonitrile for chromatography R